This invention relates to a method for manufacturing floating type thin film magnetic heads, and more particularly to a method for manufacturing such magnetic heads which characteristically comprises the steps of ion-etching the recording medium-facing plane surface of the respective narrow parallelepiped core blocks cut out of a core block stock made of a ferrite or ceramic to provide an air bearing surface with high precision for a plurality of magnetic heads which are later cut off of said core blocks.
Hitherto, the floating type thin film magnetic head has been manufactured from a plurality of narrow parallelepiped core blocks cut out of a core block stock made of a ferrite or ceramic by machining the recording medium-facing plane of the head. In this case, the machining of the recording medium-facing slider surfaces, especially the air-bearing portions of said slider surfaces, has been subject to a considerable limitation with respect to the width of said air-bearing portions, depending on the height to which the head is to be floated. In other words, the above-mentioned machining has been carried out under the extremely rigid restriction which should not be exceeded in any case. The thin film transducer is typically formed of two electrodes, a magnetic material such as permalloy and two conductors as shown in FIG. 2 of enlarged scale. Generally, only a very small margin is allowed for a space between the air bearing surface and the transducer, presenting considerable difficulties in the above-mentioned machining.
U.S. Pat. No. 4,045,864 for a magnetic head-manufacturing method discloses a process of providing a read-write gap. According to this method, that portion of a core block which corresponds to the width of said gap is etched off, and then the gap is finally defined by glass-bonding the said etched portion. The gap is made so as to have a width corresponding to the extent of said etching. The etching is carried out by an ion beam process or plasma process.